Method for hemodynamic stimulation and monitoring

ABSTRACT

The present invention is directed toward a method for stimulating and/or monitoring hemodynamic activity, such as blood flow, in a penis. The method of the present invention comprises the coupling of an ultrasound source to the outer surface of the penis and transmitting ultrasound energy into the penis at a sufficient frequency and intensity to increase hemodynamic activity. An apparatus is also provided for practicing the method of the present invention. The apparatus provides for position adjustment of the ultrasound transducers during the circumferential expansion of the penis resulting from increased hemodynamic activity.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed toward a method and apparatus forstimulating and/or monitoring hemodynamic activity, such as blood flow,in a penis. The method of the present invention comprises the couplingof an ultrasound source to the outer surface of the penis andtransmitting ultrasound energy into the penis at a sufficient frequencyand intensity to increase hemodynamic activity. An apparatus is alsoprovided for practicing the method of the present invention. Theapparatus provides for position adjustment of the ultrasound transducersduring the circumferential expansion of the penis resulting fromincreased hemodynamic activity.

2. Description of the Prior Art

Erectile dysfunctionality may result from neurogenic, vasculogenic,hormonal, and/or psychogenic causes. The term "erectiledysfunctionality", as used herein, refers to the inability or impairedability of a male patient to experience a penile erection. Theurological arts have devised a number of therapies for treating erectiledysfunctionality. These therapies include psychological,pharmacological, and electrical therapies.

A method and device for electrically stimulating a penile erection isdisclosed in U.S. Pat. No. 4,585,005 to Lue et al. The method disclosedin Lue includes the implantation of an electrode on the cavernous nerve.The electrodes of Lue are connected to a receiver that is subcutaneouslyimplanted in the patient. The method and device disclosed in Luerequires surgery. Additionally, if the device disclosed in Luemalfunctions, surgery is required to remove it. Surgery is expensive andtime consuming. Additionally, many patients may have emotional orpsychological aversions to having electrodes implanted in their penis.

An apparatus for electrically stimulating penile tissue to cause apenile erection is disclosed in U.S. Pat. No. 5,571,118 to Boutos.Boutos discloses the use of a ring having a conductive surface that isplaced on the penis and/or the scrotum. There is a risk that such adevice may short circuit, if used in an electrically conductiveenvironment, such as a hot tub. This is a major drawback of externalelectrical therapies, as contrasted with external ultrasound therapies.The use of ultrasound transducers on submerged patients has been appliedin other nonanalogous arts, such as extracorporeal shock wavelithotripsy.

An apparatus for electrically stimulating a penile erection is disclosedin U.S. Pat. Nos. 4,542,753 and 4,663,102 to Brennan et al. Brennandiscloses a body member for insertion into the rectum of a patient. Thebody member comprises surface mounted electrodes. Brennan teachesinsertion of the body member sufficiently deep into the patient for atleast one electrode to contact the prostate gland. The device disclosedby Brennan is highly invasive. Patients may experience physicaldiscomfort from the rectal insertion of the device disclosed in Brennan.

Pharmacological therapies for erectile dysfunctionality include theinjection of drugs into the penis. Such methods are disclosed in U.S.Pat. No. 5,236,904 to Gerstengerg et al. and U.S. Pat. No. 4,127,118 toLatorre. Many male patients find the thought of jabbing a hypodermicneedle into their penis to be discomforting. Penile injections may alsoresult in the buildup of scar tissue, bleeding, and persistent prolongederection (priapism). The unacceptability of therapies requiring theintracavernosal injection of drugs into the penis is well documented inthe urological arts (See U.S. Pat. No. 5,482,039 to Place et al.; andPadma-Nathan, Treatment of Men With Erectile Dysfunction WithTransurethral Alprostadil, The New England Journal of Medicine, 336:1-7,Jan. 2, 1997).

Other pharmacological therapies for erectile dysfunctionality includedelivering a drug directly into the urethra of a patient. Methods anddevices for transurethral delivery of drugs into the penis are disclosedin U.S. Pat. Nos. 5,242,391 and 5,482,039 to Place et al. Thesetransurethral drug delivery methods involve inserting a shaft into theurethra. The insertion of a shaft up the urethra may cause discomfort inmany patients or be objectionable for many of the same reasons thatpenile hypodermic needle injections are objectionable.

The present invention provides an ultrasonic therapy for hemodynamicstimulation of the penis that does not require (1) the injection ofdrugs into the penis, (2) surgical implantation of electrodes into thepenis, or (3) the insertion of electrodes into the rectum. The method ofthe present invention may be practiced in an electrically conductivemedium without the short circuiting risk present in prior art methods ofelectrotherapy for erectile dysfunctionality.

SUMMARY OF THE INVENTION

Blood is the hydraulic driving fluid that provides the mass increase andforce which result in a penile erection. Under normal conditions, apenile erection occurs when the mass flow rate of blood into the penisexceeds the mass flow rate of blood out of the penis for a certain timeinterval. Vasculogenic erectile dysfunctionality may result from arestriction or blockage of blood flow into the penis or from excessblood flow out of the penis. The present invention is aimed at treatingvasculogenic erectile dysfunctionality that results from inadequateblood flow into the penis. The present invention may also be used withdevices intended to restrict the venous outflow of blood from the penis,such as the venous flow controller sold under the trademark ACTIS byVivus, Inc. of Menlo Park, Calif.

The present invention provides a method for stimulating hemodynamicactivity within a penis. The first method step of the present inventionis coupling an ultrasound source to the outer surface of a penis. Thesecond method step of the present invention is transmitting ultrasoundenergy into the penis at a sufficient frequency and intensity toincrease hemodynamic flow within the penis.

A portion of the ultrasound energy transmitted into the body isconverted to thermal energy. The increased blood flow resulting from theuse of the present invention provides a thermal transport medium fortransporting and dispersing thermal energy introduced from thetransmission of ultrasound energy. This thermal transport helps tominimize localized temperature increases within the penis.

The present invention also provides a method for monitoring the effectof the stimulation therapy of the present invention. The presentinvention also includes ultrasonographically measuring one or morehemodynamic parameters within the penis. These hemdynamic parameters mayinclude blood flow velocity, blood pressure, and/or blood temperature.The measured hemodynamic parameters can be graphically displayed toprovide a real time indication of hemodynamic and/or thermal-hydraulicparameters within the penis. The measured hemodynamic parameters may betransmitted to a remote terminal for analysis by a remotely locatedhealth care professional. Alternatively, the measured hemodynamicparameters may be analyzed by an expert system located either remotelyor with the patient.

The present invention is also directed toward an apparatus forstimulating hemodynamic activity within a penis. The apparatus of thepresent invention comprises an ultrasound generator, and a portablehousing coupled to the ultrasound generator. The housing comprises atleast one ultrasound trigger and a lower transducer mounting assembly.The invention further comprises an axial position adjuster coupled tothe lower transducer mounting assembly and an upper transducer mountingassembly mounted above and in alignment with the lower transducermounting assembly. The upper transducer mounting assembly is coupled tothe axial position adjuster.

A lower ultrasound emitter is mounted in the lower transducer mountingassembly. The lower ultrasound emitter is connected to the ultrasoundtrigger and to the ultrasound generator. An upper ultrasound emitter ismounted in the upper transducer mounting assembly. The upper ultrasoundemitter is connected to the ultrasound trigger and to the ultrasoundgenerator. The apparatus of the present invention may also be used toultrasonographically measure one or more penile hemodynamic parameters.

DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram of a first method embodiment of the presentinvention.

FIG. 1B is a block diagram of a second method embodiment of the presentinvention.

FIG. 2 is a side view of a first apparatus embodiment of the presentinvention.

FIG. 3 is a block diagram of a second apparatus embodiment of thepresent invention.

FIG. 4 is a side cross sectional view of the rotatable adjusting wheelof the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The apparatus of the present invention comprises an ultrasound generator9 and a portable housing 10 coupled to the ultrasound generator, asshown in FIG. 2. The portable housing comprises at least one ultrasoundtrigger 11 and a lower transducer mounting assembly 18. In a preferredembodiment, the lower transducer mounting assembly is curved.

In a preferred embodiment, the ultrasound generator is capable ofselectively generating pulsed or continuous wave ultrasound energy. Thisselective generation may be accomplished by a control knob or switch 8,as shown in FIG. 2. In a preferred embodiment, the ultrasound generatorfurther comprises frequency controls 6 and intensity controls 7, asshown in FIG. 2.

An axial position adjuster is coupled to the lower transducer mountingassembly. In the preferred embodiment shown in FIGS. 2 and 4, theadjuster comprises a threaded rod 14 and a rotatable adjusting wheel 16,comprising a centrally located female threaded channel 17. The channelthreadably engages the rod such that when the wheel is rotated, the rodis axially displaced.

It is known in the ultrasound arts that a satisfactory ultrasoundcoupling is necessary for effective delivery of ultrasound energy to apatient for therapeutic or diagnostic purposes. The axial positionadjuster provides a mechanism for maintaining a satisfactory ultrasoundcoupling as the penis expands circumferentially as a result of increasedhemodynamic activity. The axial position adjuster also makes the presentinvention suitable for use with different patients having variedphysical sizes.

The apparatus and method of the present invention may be practiced bythe patient, after proper training, without assistance from anotherperson. In the preferred embodiment shown in FIG. 2, the portablehousing has a pistol type grip, thereby allowing the patient to operatethe trigger or triggers with one hand, while manipulating the axialposition adjuster with the other hand as needed to maintain a suitableultrasound coupling during penile expansion. The placement of thetriggers and axial position adjuster on opposite sides of the housingfacilitates the patient's ability to comfortably use both hands tosimultaneously manipulate the trigger and axial position adjuster.

The invention further comprises an upper transducer mounting assembly 24mounted above, and in alignment with, the lower transducer mountingassembly. In a preferred embodiment, the upper transducer mountingassembly is curved. The upper transducer mounting assembly is coupled tothe axial position adjuster. The radii of curvature of the upper andlower transducer mounting assemblies are sized such that the upper andlower transducers can be coupled to the outer surface of a penis. Asshown in FIG. 2, the apparatus of the present invention does notcomprise an enclosure that isolates the penis from ambient conditions.Accordingly a penis inserted between the upper and lower transducermounting assemblies will be exposed to ambient pressure conditions.

A lower ultrasound emitter 19 is mounted in the lower transducermounting assembly. The lower emitter is connected to the ultrasoundtrigger and to the ultrasound generator. Electrical and/or electroniccircuitry suitable for connecting ultrasound transmitters to anultrasound generator are described in the following U.S. patents: U.S.Pat. No. 3,735,756 to Richards; U.S. Pat. No. 5,578,060 to Pohl et al.;and U.S. Pat. No. 4,484,569 to Driller et al. The full disclosures ofthese U.S. patents is incorporated herein by reference.

An upper ultrasound emitter 22 is mounted in the upper transducermounting assembly, as shown in FIG. 2. The upper ultrasound emitter isconnected to the ultrasound trigger and to the ultrasound generator. Ina preferred embodiment, the upper and lower ultrasound emitters comprisea multiplicity of transducers, as shown in FIG. 2.

In the preferred embodiment shown in FIGS. 2-3, the invention furthercomprises an ultrasonography generator 30 connected to at least onetransducer in each transducer mounting assembly and an ultrasonographytrigger 12 mounted in the portable housing and connected to theultrasonography generator. In a preferred embodiment the ultrasonographygenerator and the ultrasound generator are each connected to at leasttwo ultrasound transducers in each of the transducer mountingassemblies.

The ultrasonography generator is suitable for monitoring penilehemodynamic parameters, such as blood flow. Ultrasonographic apparatussuitable for use with the present invention are disclosed in thefollowing U.S. patents: U.S. Pat. No. 4,612,937 to Miller; and U.S. Pat.No. 4,334,543 to Fehr. The full disclosures of these two patents areincorporated herein by reference. The ultrasonography generator maycomprise a display 32 for displaying measured hemodynamic parametersand/or an expert system 33 capable of analyzing measured hemodynamicparameters. The expert system is capable of comparing one or moremeasured hemodynamic parameters to preestablished parameter limits, suchas maximum blood pressure. The expert system is further capable ofgenerating an instruction to the user to stop ultrasound therapy if thepredetermined limits are exceeded. These instructions can be generatedvia the display on the ultrasonography generator or other visual oraudible means of communication.

In another preferred embodiment, the expert system is capable ofgenerating an open circuit signal to the ultrasound generator in theevent that preestablished limits are exceeded for selected hemodynamicparameters. In this embodiment, the expert system functions as a controlcircuit for the ultrasound generator.

In a preferred embodiment, measured hemodynamic parameters may also betransmitted to a remote location by a variety of data transmissionmeans, including telephone lines and wireless communication.Transmission to remote location may permit active participation of ahealth care professional while the patient practices the method of thepresent invention.

The present invention also provides a method for stimulating hemodynamicactivity within a penis, as shown in FIGS. 1A-1B. The method comprisescoupling an ultrasound source to the outer surface of a penis, as shownin block 40 of FIG. 1A. In a preferred embodiment the source ofultrasound energy comprises at least two ultrasound transducers, placedon opposite sides of the penis, as shown in FIG. 2. In another preferredembodiment the source of ultrasound energy comprises a portable housingcomprising the transducers.

The method further comprises transmitting ultrasound energy into thepenis at a sufficient frequency and intensity to increase hemodynamicflow within the penis, as shown in block 42 of FIG. 1A. The transmissionof ultrasound energy may be either pulsed or continuous. In a preferredembodiment the invention further comprises restricting the venousoutflow of blood from the penis, as shown in block 44 of FIG. 1A.

Another embodiment of the method invention is shown in FIG. 1B. In thisembodiment an ultrasound coupling gel or fluid is applied to the outersurface of a penis, as shown in block 50 of FIG. 1B. A source of pulsedultrasound energy is placed against the outer surface of the penis, asshown in block 52 of FIG. 1B. The method further comprises transmittingpulsed ultrasound energy through the coupling gel or fluid and into thepenis at a sufficient frequency and intensity to increase hemodynamicflow within the penis, as shown in block 54 of FIG. 1B. The next step ofthe method of this embodiment of the invention is ultrasonographicallymeasuring one or more hemodynamic parameters within the penis, as shownin block 56 of FIG. 1B.

In a preferred embodiment the ultrasonographic measuring comprises ameasurement of blood flow velocity. In another preferred embodiment thetransmitting and measuring steps are repeated in alternating series, asshown in block 58 of FIG. 1B. In a preferred embodiment, the inventionfurther comprises displaying said measured hemodynamic parameters, asshown in block 60 of FIG. 1B. In another preferred embodiment, theinvention comprises comparing one or more measured hemodynamicparameters to preestablished parameter limits, as shown in block 62 ofFIG. 1B. This comparison may be performed with an expert systemcomprising a memory containing preestablished parameter limits. Otherprogrammable controllers known in the instrumentation and control artsmay be used to accomplish the comparison step depicted in block 62 ofFIG. 1B. The comparison step may be used to provide an input to acontrol circuit used to control the ultrasound generator.

The embodiments of the invention disclosed herein are illustrative andexplanatory. Various changes in size, shape, material, as well as in thedetails of construction illustrated herein may be made without departingfrom the scope of the invention.

What is claimed is:
 1. A method for injecting ultrasound energy into apenis comprising:a. coupling an ultrasound source to the outer surfaceof a penis, said source comprising a lower transducer mounting assemblyand an upper transducer mounting assembly mounted above and in alignmentwith said lower transducer mounting assembly, each of said mountingassemblies comprising one or more transducers, and an axial positionadjuster connecting said assemblies, said adjuster being capable ofadjusting the distance between said mounting assemblies; and b.transmitting ultrasound energy into the penis.
 2. The method of claim 1,further comprising restricting the venous outflow of blood from thepenis.
 3. The method of claim 1, wherein said transmitting comprisestransmitting pulsed ultrasound energy.
 4. The method of claim 1, whereinsaid coupling comprises:a. applying a coupling gel or fluid to theexterior of the penis; and b. placing said transducers against theportion of said penis on which said coupling gel or fluid has beenapplied.
 5. The method of claim 1 further comprising adjusting theposition of the transducers to maintain a satisfactory ultrasoundcoupling as the penis expands circumferentially.
 6. The method of claim5, wherein said adjusting is performed simultaneously with saidtransmitting.
 7. A method for injecting ultrasound energy into a penisand monitoring hemodynamic activity within a penis comprising:a.applying an ultrasound coupling gel or fluid to the outer surface of apenis; b. placing a source of pulsed ultrasound energy against the outersurface of the penis; c. transmitting pulsed ultrasound energy throughsaid coupling gel or fluid and into the penis; and d.ultrasonographically measuring one or more hemodynamic parameters withinthe penis.
 8. The method of claim 7, further comprising comparing one ormore measured hemodynamic parameters to preestablished parameter limits.9. The method of claim 8, wherein said ultrasonographic measuringcomprises a measurement of blood flow velocity or blood pressure. 10.The method of claim 8, further comprising displaying said measuredhemodynamic parameters.
 11. The method of claim 8 wherein said comparingis performed by an expert system comprising at least one preestablishedhemodynamic parameter limit.
 12. The method of claim 11 furthercomprising controlling said transmitting with a control signal producedby said expert system.
 13. The method of claim 11 further comprisinggenerating an instruction to the user to stop transmitting when at leastone parameter limit is exceeded.
 14. The method of claim 7, wherein saidultrasonographically measuring comprises measuring with a set ofdiagnostic transducers.
 15. The method of claim 7, further comprisingrepeating said transmitting and said measuring in alternating series.16. A method for monitoring hemodynamic activity within a penis exposedto ambient pressure conditions, comprising:a. coupling an ultrasoundsource to the outer surface of a penis exposed to ambient pressureconditions; and b. transmitting ultrasound energy into a penis exposedto ambient pressure conditions; and c. ultrasonographically measuringone or more hemodynamic paramaters within the penis exposed to ambientpressure conditions.
 17. The method of claim 16 further comprising:a.comparing at least one hemodynamic parameter to at least onepreestablished parameter limit; b. generating a control signal basedupon said comparison; and c. controlling said transmitting with saidcontrol signal.